LIGHT

he world is largely known through

the senses. The sense of sight

is one of the most important

senses. Through it we see mountains,

rivers, trees, plants, chairs, people and

so many other things around us. We also

see clouds, rainbows and birds flying

in the sky. At night we see the moon

and the stars. You are able to see the

words and sentences printed on this

page. How is seeing made possible?

13.1 What makes Things

Visible

Have you ever thought how we see

various objects? You may say that eyes

see the objects. But, can you see an

object in the dark? It means that eyes

alone cannot see any object. It is only

when light from an object enters our

eyes that we see the object. The light

may have been emitted by the object, or

may have been reflected by it.

You learnt in Class VII that a polished

or a shiny surface can act as a mirr

or. A

mirror changes the direction of light

that falls on it. Can you tell in which

dir

ection the light falling on a surface

will be reflected? Let us find out.

13.2 Laws of Reflection

Activity 13.1

Fix a white sheet of paper on a

drawing board or a table. Take a

comb and close all its openings

except one in the middle. You can

use a strip of black paper for

this purpose. Hold the comb

perpendicular to the sheet of paper.

Throw light from a torch through

the opening of the comb from one

side (Fig. 13.1). With slight

adjustment of the torch and the

comb you will see a ray of light along

the paper on the other side of the

comb. Keep the comb and the torch

steady. Place a strip of plane mirror

in the path of the light ray

(Fig. 13.1). What do you observe?

After striking the mirror, the ray of

light is reflected in another direction.

The light ray, which strikes any surface,

is called the incident ray. The ray that

comes back from the surface after

reflection is known as the reflected ray.

Fig. 13.1 : Arrangement for showing reflection

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A ray of light is an idealisation. In

reality, we have a narrow beam of

light which is made up of several

rays. For simplicity, we use the term

ray for a narrow beam of light.

Draw lines showing the position of

the plane mirror, the incident ray and

the reflected ray on the paper with the

help of your friends. Remove the mirror

and the comb. Draw a line making an

angle of 90º to the line representing the

mirror at the point where the incident

ray strikes the mirror. This line is known

as the nor

mal

to the reflecting surface

at that point (Fig. 13.2). The angle

Table 13.1 : Angles of Incidence

and Reflection

S. Angle of

Angle of

No. Incidence (

∠

∠i) Reflection (

∠

∠∠

∠r)

Do you see any relation between the

angle of incidence and the angle of

reflection. Are they approximately equal?

If the experiment is carried out carefully,

it is seen that the angle of incidence is

always equal to the angle of reflection.

This is one of the

laws of reflection

Let us perform another activity on

reflection.

What would happen if I

threw the light on the

mirror along the normal.

Activity 13.2

Perform Activity 13.1 again. This

time use a sheet of stiff paper or a

chart paper. Let the sheet project a

little beyond the edge of the Table

(Fig. 13.4). Cut the projecting

portion of the sheet in the middle.

Look at the reflected ray. Make sure

that the reflected ray extends to the

projected portion of the paper. Bend

that part of the projected portion on

which the reflected ray falls. Can

you still see the reflected ray? Bring

the paper back to the original

Fig. 13.2 : Drawing the normal

Fig. 13.3 : Angle of incidence and angle of

reflection

Reflected

ray

Normal

Incident

ray

between the normal and incident ray is

called the angle of incidence (

∠∠

∠i). The

angle between the normal and the

reflected ray is known as the

angle of

reflection (

∠∠

∠r) (Fig. 13.3). Measure the

angle of incidence and the angle of

reflection. Repeat the activity several

times by changing the angle of

incidence. Enter the data in Table 13.1.

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167

position. Can you see the reflected

ray again? What do you infer?

with the Sun as the source of light

instead of a torch. You, too, can use the

Sun as the source of light.

These activities can also be performed

by making use of the Ray Streak

Apparatus (available in the kit

prepar

ed by NCERT).

Boojho remembered that in Class VII,

he had studied some features of the

image of an object formed by a plane

mirror. Paheli asked him to recall

those features:

(i) Was the image erect or upside

down?

(ii) Was it of the same size as the

object?

(iii) Did the image appear at the same

distance behind the mirror as the

object was in front of it?

(iv) Could it be obtained on a screen?

Let us understand a little more about

the formation of an image by a plane

mirror in the following way:

Activity 13.3

A source of light O is placed in front

of a plane mirror PQ. Two rays OA

and OC are incident on it (Fig. 13.5).

Can you find out the direction of

the reflected rays?

Draw normals to the surface of

the mirror PQ, at the points A and

C. Then draw the reflected rays at

the points A and C. How would you

draw these rays? Call the reflected

rays AB and CD, respectively.

Extend them further. Do they meet?

Extend them backwards. Do they

meet now? If they meet, mark this

point as I. For a viewer’s eye at E

(Fig. 13 .5), do the reflected rays

(b)

Fig. 13.4 (a), (b) : Incident ray, reflected ray

and the normal at the point

of incidence lie in the same

plane

When the whole sheet of paper is

spread on the table, it represents one

plane. The incident ray, the normal at

the point of incidence and the reflected

ray are all in this plane. When you bend

the paper you create a plane different

from the plane in which the incident

ray and the normal lie. Then you do not

see the reflected ray. What does it

indicate? It indicates that the incident

ray, the normal at the point of

incidence and the reflected ray all lie

in the same plane. This is another law

of reflection.

Paheli and Boojho performed the

above activities outside the classroom

(a)

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appear to come from the point I.

Since the reflected rays do not

actually meet at I, but only appear

to do so, we say that a virtual image

of the point O is formed at I. As you

have learnt already in Class VII,

such an image cannot be obtained

on a screen.

You may recall that in an image

formed by a mirror the left of the object

appears on the right and the right

appears on the left. This is known as

lateral inversion.

13.3 Regular and Diffused

Reflection

Activity 13.4

Imagine that parallel rays are

incident on an irregular surface as

shown in Fig. 13.6. Remember that

the laws of reflection are valid at

each point of the surface. Use these

laws to construct reflected rays at

various points. Are they parallel to

one another? You will find that

these rays are reflected in different

directions. (Fig. 13.7)

When all the parallel rays reflected

from a rough or irregular surface are

not parallel, the reflection is known as

diffused or irregular reflection.

Remember that the diffused reflection

is not due to the failure of the laws of

reflection. It is caused by the

irregularities in the reflecting surface,

like that of a cardboard.

On the other hand, reflection from

a smooth surface like that of a

mirror is called regular reflection

(Fig. 13.8). Images are formed by

regular reflection.

Fig. 13.5 : Image formation in a plane mirror

Fig. 13.6 : Parallel rays incident on

an irregular surface

Fig. 13.7 : Rays reflected from irregular

surface

Fig. 13.8 : Regular reflection

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Let us find out.

13.4 Reflected Light Can be

Reflected Again

Recall the last time you visited a hair

dresser. She/he makes you sit in front of

a mirror. After your hair cut is complete,

she/he holds a mirror behind you to show

you how the hair has been cut

(Fig. 13.9).

Do you know how you could

see the hair at the back of your head?

Paheli recalls having constructed a

periscope as an Extended Activity in

Class VI. The periscope makes use of

two plane mirrors. Can you explain

how reflection from the two mirrors

enables you to see objects which are

not visible directly? Periscopes are

used in submarines, tanks and also

by soldiers in bunkers to see things

outside.

13.5 Multiple Images

You are aware that a plane mirror forms

only a single image of an object. What

happens if two plane mirrors are used

in combination? Let us see.

Do We See all Objects due to Reflected Light?

Nearly everything you see around is seen due to reflected light. Moon, for example,

receives light from the Sun and reflects it. That’s how we see the moon. The objects

which shine in the light of other objects are called illuminated objects. Can you

name some other such objects?

There are other objects, which give their own light, such as the Sun, fire, flame

of a candle and an electric lamp. Their light falls on our eyes. That is how we see

them. The objects which emit their own light are known as luminous objects.

Fig. 13.9 : Mirror at the hair dresser shop

I have a question. Can the

reflected rays be further reflected

if incident on another mirror?

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Activity 13.5

Take two plane mirrors. Set them

at right angles to each other with

their edges touching (Fig. 13.10). To

hinge them you can use adhesive

tape. Place a coin in between the

mirrors. How many images of the

coin do you see (Fig. 13.10)?

Now hinge the mirrors using the

adhesive tape at different angles, say

45°, 60°, 120°, 180° etc. Place some

object (say a candle) in between

them. Note down the number of

images of the object in each case.

Finally, set the two mirrors

parallel to each other. Find out

how many images of a candle

placed between them are formed

(Fig. 13.11).

Fig. 13.10 : Images in plane mirror at right

angle to each other

Fig. 13.11 : Image in plane mirror parallel

to each other

mirrors

(a)

(b)

(c)

Can you now explain how you can

see the back of your head at the hair

dresser’s shop?

This idea of number of images formed

by mirrors placed at an angle to one

another is used in a kaleidoscope to

make numerous beautiful patterns. You

can also make a kaleidoscope yourself.

Kaleidoscope

Activity 13.6

To make a kaleidoscope, get three

rectangular mirror strips each about

15 cm long and 4 cm wide. Join

them together to form a prism as

shown in Fig. 13.12(a). Fix this

arrangement of mirrors in a circular

cardboard tube or tube of a thick

chart paper. Make sure that the tube

is slightly longer than the mirror

strips. Close one end of the tube by

a cardboard disc having a hole in

the centre, through which you can

see [Fig. 13.12(b)]. To make the disc

durable, paste a piece of transparent

plastic sheet under the cardboard

Fig. 13.12 : Making a kaleidoscope

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disc. At the other end, touching the

mirrors, fix a circular plane glass

plate [Fig. 13.12(c)]. Place on this

glass plate several small pieces of

coloured glass (broken pieces of

coloured bangles). Close this end of

the tube by a ground glass plate.

Allow enough space for the colour

pieces to move around.

Your kaleidoscope is ready. When

you peep through the hole, you will be

able to see a variety of patterns in the

tube. An interesting feature of a

kaleidoscope is that you will never see

the same pattern again. Designers of

wallpapers and fabrics and artists often

use kaleidoscopes to get ideas for new

patterns. To make your toy attractive,

you can wrap the kaleidoscope in a

colour

ed paper.

13.6 Sunlight — White or

Coloured

In Class VII, you learnt that the sunlight

is referr

ed to as white light. You also

learnt that it consists of seven colours.

Here is another activity (Activity 13.7)

showing that sunlight consists of several

colours.

13.7 What is inside Our Eyes?

We see things only when light coming

from them enters our eyes. Eye is one

of our most important sense organs. It

is, therefore, important to understand

its structure and working.

The eye has a roughly spherical

shape. The outer coat of the eye is

white. It is tough so that it can protect

the interior of the eye from accidents.

Its transparent front part is called

Activity 13.7

Fig. 13.13 : Dispersion of light

Get a plane mirror of a suitable size.

Place it in a bowl (katori) as shown

in Fig. 13.13. Fill the bowl with

water. Put this arrangement near a

window in such a way that direct

sunlight falls on the mirror. Adjust

the position of the

bowl so that the

reflected light from

the mirror falls on

a wall. If the wall is

not white, fix a sheet

of white paper on it.

Reflected light will

be seen to have

many colours. How

can you explain

this? The mirror

and water form a

prism. As you learnt in Class VII,

this breaks up the light into its

colours, Splitting of light into its

colours is known as dispersion of

light. Rainbow is a natural

phenomenon showing dispersion.

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Fig. 13.15 : Demonstration of blind spot

Caution : For this activity, never use

a laser torch.

Activity 13.8

Look into your friend’s eye. Observe

the size of the pupil. Throw light on

her eye with a torch. Observe the

pupil now. Switch off the torch, and

observe her pupil once again. Do

you notice any change in the size

of the pupil? In which case was the

pupil larger? Why do you think it

was so?

In which case do you need to

allow more light in the eye, when

the light is dim or bright?

Behind the pupil of the eye is a lens

which is thicker in the centre. What

kind of lens is thicker at the centre?

Recall what you learnt about lenses in

cornea (Fig. 13.14). Behind the cornea,

we find a dark muscular structure

called iris. In the iris, there is a small

opening called the pupil. The size of

the pupil is controlled by the iris. The

iris is that part of eye which gives it its

distinctive colour. When we say that a

person has green eyes, we refer actually

to the colour of the iris. The iris controls

the amount of light entering into the

eye. Let us see how.

Iris

Lens

Ciliary

muscle

Cornea

Retina

Optic

Nerve

Fig. 13.14 : Human eye

Class VII. The lens focuses light on the

back of the eye, on a layer called retina

(Fig. 13.14). The retina contains several

nerve cells. Sensations felt by the nerve

cells are then transmitted to the brain

through the optic nerve. There are two

kinds of cells–

(i) cones, which are sensitive to bright

light and

(ii) rods, which are sensitive to dim light.

Cones sense colour. At the junction

of the optic nerve and the retina, there

are no sensory cells, so no vision is

possible at that spot. This is called the

blind spot. Its existence can be

demonstrated as follows:

Activity 13.9

Make a round mark and a cross on

a sheet of paper with the spot to the

right of the cross (Fig. 13.15). The

distance between two marks may be

6-8 cm. Hold the sheet of paper at

an arm’s length from the eye. Close

your left eye. Look continuously at

the cross. Move the sheet slowly

towards you, keeping your eye on

the cross. What do you find? Does

the round mark disappear at some

point? Now close your right eye.

Look at the round mark now and

repeat the activity. Does the cross

disappear? The disappearance of the

cross or the round mark shows that

there is a point on the retina which

cannot send messages to the brain

when light falls on it.

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Nature has provided eyes with

eyelids to prevent any object from

entering the eye. Eyelids also shut out

light when not required.

Eye is such a wonderful instrument

that it (normal) can clearly

see distant

objects as well as objects nearby. The

minimum distance at which the eye can

see objects distinctly varies with age. The

most comfortable distance at which one

can read with a normal eye is about

25 cm.

Some persons can see objects close

to them clearly but cannot see distant

objects so clearly. On the other hand,

some persons cannot see objects nearby

clearly but they can see distant objects

quite well. With suitable corrective

lenses, these defects of the eye can

be corrected.

Sometimes, particularly in old age,

eyesight becomes foggy. It is due to the

eye lens becoming cloudy. When it

happens, persons are said to have

cataract. There is a loss of vision,

sometimes extremely severe. It is

possible to treat this defect. The opaque

lens is removed and a new artificial

lens is inserted. Modern technology

has made this procedure simpler

and safer.

13.8 Care of the Eyes

It is necessary that you take proper care

of your eyes. If there is any problem

you should go to an eye specialist. Have

a regular checkup—

l If advised, use suitable spectacles.

l Too little or too much light is bad

for eyes. Insufficient light causes

eyestrain and headaches. Too much

light, like that of the Sun, a powerful

The movies that we see are actually

a number of separate pictures in

proper sequence. They are made to

move across the eye usually at the rate

of 24 pictures per second (faster

than 16 per second). So, we see a

moving picture.

Front side of

cardboard

Reverse side

of cardboard

The impression of an image does not

vanish immediately from the retina. It

persists there for about 1/16th of a

second. So, if still images of a moving

object are flashed on the eye at a rate

faster than 16 per second, then the eye

perceives this object as moving.

Activity 13.10

Get a square piece of cardboard of

size 6-8 cm. Make two holes as

shown in Fig. 13.16. Thread a

string through the two holes. Draw/

paste a cage on one side of the

cardboard and a bird on the other

side. Twist the string and make the

card twirl rapidly. Do you see the

bird in the cage?

Fig. 13.16 : Bird in cage

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lamp or a laser torch can injure the

retina.

l Do not look at the Sun or a powerful

light directly.

l Never rub your eyes. If particles of

dust go into your eyes, wash your

eyes with clean water. If there is no

improvement go to a doctor.

l Always read at the normal distance

for vision. Do not read by bringing

the book too close to your eyes or

keeping it too far.

You learnt about balanced diet in

Class VI. If food is deficient in some

components, eyes may also suffer. Lack

of vitamin A in foodstuff is responsible

for many eye troubles. Most common

amongst them is night blindness.

One should, therefore, include in the

diet components which have vitamin A.

Raw carrots, broccoli and green

Did you know?

Animals have eyes shaped in different ways. Eyes of a crab are quite small but

they enable the crab to look all around. So, the crab can sense even if the enemy

approaches from behind. Butterflies have large eyes that seem to be made up

of thousands of little eyes

(Fig. 13.17). They can see not only

in the front and the sides but the

back as well.

A night bird (owl) can see very

well in the night but not during

the day. On the other hand, day

light birds (kite, eagle) can see

well during the day but not in the

night. The owl has a large cornea

and a large pupil to allow more

light in its eye. Also, it has on its

retina a large number of rods and

only a few cones. The day birds

on the other hand, have more

cones and fewer rods.

Fig. 13.17 : Eyes of a butterfly

Eyes

vegetables (such as spinach) and cod

liver oil are rich in vitamin A. Eggs,

milk, curd, cheese, butter and fruits

such as papaya and mango are also rich

in vitamin A.

13.9 Visually Impaired

Persons Can Read and

Write

Some persons, including children, can

be visually impaired. They have very

limited vision to see things. Some

persons cannot see at all since birth.

Some persons may lose their eyesight

because of a disease or an injury. Such

persons try to identify things by

touching and listening to voices more

carefully. They develop their other

senses more sharply. However,

additional resources can enable them

to develop their capabilities further.

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13.10 What is the Braille

System?

The most popular resource for visually

challenged persons is Braille.

Louis Braille

Louis Braille, himself a visually

challenged person, developed a

system for visually challenged persons

and published it in 1821.

Non-optical and optical aids for visually impaired

Non-optical aids include visual aids, tactual aids (using the sense of touch), auditory

aids (using the sense of hearing) and electronic aids. Visual aids, can magnify

words, can provide suitable intensity of light and material at proper distances.

Tactual aids, including Braille writer slate and stylus, help the visually challenged

persons in taking notes, reading and writing. Auditory aids include cassettes, tape

recorders, talking books and other such devices. Electronic aids, such as talking

calculators and computers, are also available for performing many computational

tasks. Closed circuit television, also an electronic aid, enlarges printed material

with suitable contrast and illumination. Nowadays, use of audio CDs and voice boxes

with computers are also very helpful for listening to and writing the desired text.

Optical aids include bifocal lenses, contact lenses, tinted lenses, magnifiers

and telescopic aids. While the lens combinations are used to rectify visual

limitations, telescopic aids are available to view chalkboard and class

demonstrations.

The present system was adopted in

1932. There is Braille code for common

languages, mathematics and scientific

notation. Many Indian languages can

be read using the Braille system.

Braille system has 63 dot patterns or

characters. Each character

represents a letter, a combination of

letters, a common word or a

grammatical sign. Dots are arranged

in cells of two vertical rows of three

dots each.

Patterns of dots to represent some

English letters and some common

words are shown below.

These patterns when embossed on

Braille sheets help visually

challenged persons to recognise words

by touching. To make them easier to

touch, the dots are raised slightly.

Fig. 13.18 : Example of dot patterns used

in Braille System

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Some visually impaired Indians have great achievements to their

credit. Diwakar, a child prodigy has given amazing performances

as a singer.

Ravindra Jain, born completely visually impaired, obtained

his Sangeet Prabhakar degree from Allahabad. He had shown his

excellence as a lyricist, singer and music composer.

Lal Advani, himself visually impaired, established an

Association for special education and rehabilitation of disabled

in India. Besides this, he represented India on Braille problems

in UNESCO.

Helen A. Keller, an American author and lecturer, is perhaps the most well-

known and inspiring visually challenged person. She lost her sight when she was

only 18 months old. But because of her resolve and courage she could complete

her graduation from a university. She wrote a number of books including The

Story of my Life (1903).

Helen A. Keller

Visually impaired people learn the

Braille system by beginning with

letters, then special characters and

letter combinations. Methods depend

upon recognition by touching. Each

character has to be memorised. Braille

texts can be produced by hand or by

machine. Typewriter-like devices and

printing machines have now been

developed.

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KEYWORDSKEYWORDS

KEYWORDS

ANGLE OF

INCIDENCE

ANGLE OF

REFLECTION

BLIND SPOT

BRAILLE

CONES

CORNEA

DIFFUSED OR

IRREGULAR

REFLECTION

INCIDENT RAYS

IRIS

KALEIDOSCOPE

LATERAL INVERSION

LAWS OF

REFLECTION

PUPIL

REFLECTED RAYS

REFLECTION

REGULAR

REFLECTION

RETINA

RODS

WHAT YOU HAVE LEARNT WHAT YOU HAVE LEARNT

WHAT YOU HAVE LEARNT

Ü Light is reflected from all surfaces.

Ü Regular reflection takes place when light is

incident on smooth, polished and regular

surfaces.

Ü Diffused or irregular reflection takes place from

rough surfaces.

Ü Two laws of reflection are

(i) The angle of incidence is equal to the angle

of reflection.

(ii) Incident ray, reflected ray and the normal

drawn at the point of incidence to the

reflecting surface, lie in the same plane.

Ü Image formed in a plane mirror undergoes

lateral inversion.

Ü Two mirrors inclined to each other give multiple

images.

Ü Beautiful patterns are formed in a

kaleidoscope because of multiple reflections.

Ü Sunlight, called white light, consists of seven

colours.

Ü Splitting of light into its constituent colours is

known as dispersion.

Ü Parts of the eye are cornea, iris, pupil, lens,

retina and optic nerve.

Ü A normal eye can see nearby and distant

objects clearly.

Ü Visually impaired persons can read and write

using the Braille system.

Ü Visually impaired persons develop their other

senses more sharply to improve their interac-

tion with their environment.

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Exercises

1. Suppose you are in a dark room. Can you see objects in the room? Can

you see objects outside the room. Explain.

2. Differentiate between regular and diffused reflection. Does diffused

reflection mean the failure of the laws of reflection?

3. Mention against each of the following whether regular or diffused reflection

will take place when a beam of light strikes. Justify your answer in each

case.

(a) Polished wooden table (b) Chalk powder

spread over it

(e) Mirror (f) Piece of paper

4. State the laws of reflection.

5. Describe an activity to show that the incident ray, the reflected ray and

the normal at the point of incidence lie in the same plane.

6. Fill in the blanks in the following.

(a) A person 1 m in front of a plane mirror seems to be _______________ m

away from his image.

(b) If you touch your ____________ ear with right hand in front of a plane

mirror it will be seen in the mirror that your right ear is touched with

____________.

(d) Night birds have ____________ cones than rods in their eyes.

Choose the correct option in Questions 7 – 8

7. Angle of incidence is equal to the angle of reflection.

(a) Always (b) Sometimes

8. Image formed by a plane mirror is

(a) virtual, behind the mirror and enlarged.

(b) virtual, behind the mirror and of the same size as the object.

(d) real, behind the mirror and of the same size as the object.

9. Describe the construction of a kaleidoscope.

10. Draw a labelled sketch of the human eye.

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11. Gurmit wanted to perform Activity 13.8 using a laser torch. Her teacher

advised her not to do so. Can you explain the basis of the teacher’s advise?

12. Explain how you can take care of your eyes.

13. What is the angle of incidence of a ray if the reflected ray is at an angle of

90° to the incident ray?

14. How many images of a candle will be formed if it is placed between two

parallel plane mirrors separated by 40 cm?

15. Two mirrors meet at right angles. A ray of light is incident on one at an

angle of 30° as shown in Fig. 13.19. Draw the reflected ray from the second

mirror.

Fig. 13.19

16. Boojho stands at A just on the side of a plane mirror as shown in

Fig. 13.20. Can he see himself in the mirror? Also can he see the image of

objects situated at P, Q and R?

Fig. 13.20

17. (a) Find out the position of the image of an object situated at A in the

plane mirror (Fig. 13.21).

(b) Can Paheli at B see this image?

(d) When Paheli moves from B to C, where does the image of A move?

Fig. 13.21

E X E R C I S E S

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Extended Learning — Activities and Project

1. Make your own mirror. Take a glass strip or glass slab. Clean it and

put it on a white sheet of paper. See yourself in the glass. Next put

the glass slab on a black sheet of paper. Again look into the glass.

In which case do you see yourself better and why?

2. Make friends with some visually impaired students. Enquire from

them how they read and write. Also find out how they are able to

recognise objects, hurdles and currency notes.

3. Meet an eye specialist. Get your eye sight checked and discuss how

to take care of your eyes.

4. Survey your neighbourhood. Find out how many children below

the age of 12 years use spectacles. Find out from their parents

what, in their view, could be the reason for the weak eyesight of

their children.

Did You Know?

Eyes can be donated by any person as an invaluable gift to visually

impaired persons suffering from corneal blindness, The person may be

(a) a male or female.

(b) of any age.

(d) using spectacles.

(e) suffering from any normal disease but not AIDS, Hepatitis B or C,

rabies, leukemia, lymphoma, tetanus, cholera, encephalitis.

The eyes have to be donated within 4-6 hours after death at any

place, home or hospital.

A person who wants to donate the eyes may pledge eyes during his/her

lifetime to any registered eye bank. He/she should also inform his/her

relatives about this pledge so that they can take necessary action after

his/her death.

You can also donate a Braille kit.

Rationalised-2023-24

Notes

Rationalised-2023-24

Notes

Rationalised-2023-24